Does creatine cause hair loss? A 2025 trial that measured hair found no effect

Almost certainly not. The belief that creatine causes hair loss rests on a single 2009 study that never measured a single hair — it measured a hormone — and in 2025 the first trial designed to actually assess hair follicles found no difference between men taking creatine and men taking placebo [s2]. The most-shared supplement scare on the internet turns out to have almost nothing under it.

Where the fear came from

Trace the claim back and it always lands in the same place: a 2009 study in the Clinical Journal of Sport Medicine [s1]. Researchers gave 20 college-aged rugby players creatine or placebo in a double-blind, placebo-controlled crossover design with a six-week washout — a loading phase of 25 grams a day for seven days, then a maintenance dose of 5 grams a day for 14 days [s1]. They measured testosterone and dihydrotestosterone, or DHT, an androgen more potent than testosterone [s1].

The result that launched a thousand forum threads: DHT rose by 56% after seven days of loading and stayed 40% above baseline through the maintenance phase (p < 0.001), while the ratio of DHT to testosterone climbed 36% and then settled 22% above baseline (p < 0.01) [s1]. Testosterone itself did not change [s1].

DHT matters to hair because it is the hormone most implicated in male- and female-pattern hair loss; the standard drug for balding, finasteride, works by lowering it, as our review of hair-loss drug evidence explains. So a supplement that raised DHT sounded, on its face, like a supplement that could thin your hair. The inference is where the story falls apart.

What the 2009 study did not show

The 2009 paper measured a hormone and stopped there. It did not measure hair density, hair thickness, follicle counts or shedding — nothing about actual hair [s1]. Its authors framed the DHT finding as a reason for further investigation given how many people use creatine, not as evidence of hair loss [s1]. Between the hormone and the hair sat an assumption that no one had tested.

There were reasons for caution about the numbers themselves, too. It was one study, in 20 people, and — as the field later emphasised — it was never replicated [s3]. A 2021 review in the Journal of the International Society of Sports Nutrition that catalogued common creatine misconceptions singled this one out: the hair-loss claim rested on a lone study that measured DHT rather than hair loss, and whose central finding no subsequent work had reproduced [s3]. For more than a decade, the scare survived on a result nobody had confirmed and an outcome nobody had actually looked at.

The 2025 study that finally looked at hair

That gap closed in 2025. A randomised controlled trial, also published in the Journal of the International Society of Sports Nutrition, set out to test the hair claim head-on [s2]. Forty-five resistance-trained men aged 18 to 40 were randomly assigned to 5 grams a day of creatine monohydrate or a 5-gram maltodextrin placebo for 12 weeks, keeping their usual diet and training [s2]. Blood was drawn at baseline and 12 weeks for total testosterone, free testosterone and DHT; hair follicle health was assessed directly, using the Trichogram test and the FotoFinder imaging system to quantify hair density, follicular-unit count and cumulative hair thickness [s2].

Thirty-eight men completed the study, and the results were flat [s2]. There were no group-by-time interactions for any hormone or any hair outcome (p > 0.05) [s2]. Total testosterone rose and free testosterone fell modestly over the 12 weeks, but those shifts happened equally in both groups and so were unrelated to creatine [s2]. Critically, there were no significant differences in DHT, in the DHT-to-testosterone ratio, or in any hair-growth parameter between the creatine and placebo groups [s2]. The authors described it as the first study to directly assess hair follicle health after creatine supplementation, and concluded that it provided strong evidence against the claim that creatine contributes to hair loss [s2].

That is a direct contradiction of the mechanism the 2009 study was assumed to imply: at a standard 5-gram maintenance dose, creatine did not even move DHT, let alone hair [s2].

The honest caveats

This is one trial, in 38 men who finished, over 12 weeks [s2] — not a permanent last word, and not a study of the very high loading doses used in 2009 [s1]. Longer trials and larger samples would strengthen the picture. Someone already genetically predisposed to pattern baldness will still lose hair on the timetable their genetics set, with or without creatine; no supplement study can rule out a small individual effect it was not powered to detect. Our broader look at creatine's 2026 evidence covers the supplement's other, better-established effects and its open safety questions.

But on the specific, viral question — does creatine cause hair loss? — the balance of evidence now runs clearly the other way: a hormone finding that was never replicated [s1][s3], and a purpose-built trial that measured hair and found nothing [s2]. This is informational, not medical advice; anyone concerned about hair loss should see a clinician, who can address the causes that are actually treatable.

Sources

1. [s1] van der Merwe J, Brooks NE, Myburgh KH. Three Weeks of Creatine Monohydrate Supplementation Affects Dihydrotestosterone to Testosterone Ratio in College-Aged Rugby Players. Clinical Journal of Sport Medicine, 4 September 2009. https://doi.org/10.1097/JSM.0b013e3181b8b52f
2. [s2] Lak M, Forbes SC, Ashtary-Larky D, et al. Does creatine cause hair loss? A 12-week randomized controlled trial. Journal of the International Society of Sports Nutrition, 23 April 2025. https://doi.org/10.1080/15502783.2025.2495229
3. [s3] Antonio J, Candow DG, Forbes SC, et al. Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? Journal of the International Society of Sports Nutrition, 8 February 2021. https://doi.org/10.1186/s12970-021-00412-w